[Dnsmasq-discuss] [FEAT.REQ] Further localisation of --localise-queries

[Simon Kelley]

Alex Hermann wrote:
> Hello,
> 
> when asked for the ip-address of the local machine dnsmasq is running on, is 
> it possible to restrict dnsmasq to only give the ip address of the 
> _interface_ the request came from. At the moment with --locallise-queries, 
> dnsmasq returns all ip's corresponding to the _subnet_ the request came 
> from.
> 
> 
> If the request is unclear, here is an explanation by example:
> 
> network layout:
> every client is connected to an individual NIC on the server.
> 
> netmask common for all NIC's: 192.168.1.255
That looks like a plausible broadcast address, not a netmask.
The actual netmask is important for this.

> 
> server: eth0 192.168.1.1  <---> client1 : 192.168.1.101
>  eth1 192.168.1.2 <---> client2 : 192.168.1.102
>  eth2 192.168.1.3 <---> client3 : 192.168.1.103
>  eth3 public ip  <---> inet
> 
> All server ip's are in /etc/hosts
> 
> 
> Current situation with --localise queries:
> 
> client1 requests address of server, server returns all three local addresses 
> (in random order).
> 
> 
> Requested situation:
> 
> client1 requests address of server, response to client1 is _only_ 
> 192.168.1.1, to client2 _only_ 192.168.1.2, etc.
> 

This looks like a very strange setup: assuming that the netmask is _not_ 
255.255.255.255, then all of 192.168.1.101-103 are on the same subnet 
and belong to the same host. Isn't that an implied promise that all 
three are equivalent?

I'm trying to understand what this configuration achieves which a more 
conventional one doesn't.

Cheers,

Simon.

> 
> 
> Alex.